Field
The present application relates generally to thermoelectric (TE) thermal management (e.g., heating and/or cooling) of electrical devices including but not limited to batteries and battery cells.
Description of Related Art
Power electronics and other electrical devices, such as batteries, can be sensitive to overheating, cold temperatures, extreme temperatures, and operating temperature limits. The performance of such devices may be diminished, sometimes severely, when the devices are operated outside of recommended or optimum temperature ranges. In semiconductor devices, integrated circuit dies can overheat and malfunction. In batteries, including, for example, batteries used for automotive applications in electrified vehicles, battery cells and their components can degrade when overheated or overcooled. Such degradation can manifest itself in reduced battery storage capacity and/or reduced ability for the battery to be recharged over multiple duty cycles.
High performance batteries for use in large systems (including, for example, lithium based batteries used in electrical vehicles) have certain properties that make thermal management of the batteries and/or containment system desirable. Charging characteristics of high performance batteries change at elevated temperatures and can cause the cycle life of the batteries to decrease significantly if they are charged at too high of a temperature. For example, the cycle life of some lithium based batteries decreased by over 50% if they are repeatedly charged at about 50° C. Since cycle life can be reduced by a large amount, the lifetime cost of batteries can be greatly increased if charging temperatures are not controlled within proper limits. Also, some high performance batteries can exhibit reduced performance and can be possibly damaged if charged or operated at too low of temperatures, such as below about −30° C. Furthermore, high performance batteries and arrays of high performance batteries can experience thermal events from which the batteries can be permanently damaged or destroyed, and over temperature condition can even result in fires and other safety related events.